//========================================================================

//

// SplashFont.cc

//

// Copyright 2003-2013 Glyph & Cog, LLC

//

//========================================================================

#include <aconf.h>

#include <string.h>

#include "gmem.h"

#include "gmempp.h"

#include "SplashMath.h"

#include "SplashGlyphBitmap.h"

#include "SplashFontFile.h"

#include "SplashFont.h"

//------------------------------------------------------------------------

// font cache size parameters

#define splashFontCacheAssoc   8

#define splashFontCacheMaxSets 8

#define splashFontCacheSize    (128*1024)

//------------------------------------------------------------------------

struct SplashFontCacheTag {

  Guint c;

  short xFrac, yFrac;   // x and y fractions

  int mru;      // valid bit (0x80000000) and MRU index

  int x, y, w, h;   // offset and size of glyph

};

//------------------------------------------------------------------------

// SplashFont

//------------------------------------------------------------------------

SplashFont::SplashFont(SplashFontFile *fontFileA, SplashCoord *matA,

           SplashCoord *textMatA, GBool aaA) {

  fontFile = fontFileA;

  fontFile->incRefCnt();

  mat[0] = matA[0];

  mat[1] = matA[1];

  mat[2] = matA[2];

  mat[3] = matA[3];

  textMat[0] = textMatA[0];

  textMat[1] = textMatA[1];

  textMat[2] = textMatA[2];

  textMat[3] = textMatA[3];

  aa = aaA;

  cache = NULL;

  cacheTags = NULL;

  xMin = yMin = xMax = yMax = 0;

}

void SplashFont::initCache() {

  int i;

  // this should be (max - min + 1), but we add some padding to

  // deal with rounding errors

  glyphW = xMax - xMin + 3;

  glyphH = yMax - yMin + 3;

  if (glyphW > 1000 || glyphH > 1000) {

    // if the glyphs are too large, don't cache them -- setting the

    // cache bitmap size to something tiny will cause getGlyph() to

    // fall back to the uncached case

    glyphW = glyphH = 0;

    glyphSize = 0;

    cacheSets = 0;

    cacheAssoc = 0;

    return;

  }

  if (aa) {

    glyphSize = glyphW * glyphH;

  } else {

    glyphSize = ((glyphW + 7) >> 3) * glyphH;

  }

  // set up the glyph pixmap cache

  cacheAssoc = splashFontCacheAssoc;

  for (cacheSets = splashFontCacheMaxSets;

       cacheSets > 1 &&

   glyphSize > splashFontCacheSize / (cacheSets * cacheAssoc);

       cacheSets >>= 1) ;

  cache = (Guchar *)gmallocn(cacheSets * cacheAssoc, glyphSize);

  cacheTags = (SplashFontCacheTag *)gmallocn(cacheSets * cacheAssoc,

               sizeof(SplashFontCacheTag));

  for (i = 0; i < cacheSets * cacheAssoc; ++i) {

    cacheTags[i].mru = i & (cacheAssoc - 1);

  }

}

SplashFont::~SplashFont() {

  fontFile->decRefCnt();

  if (cache) {

    gfree(cache);

  }

  if (cacheTags) {

    gfree(cacheTags);

  }

}

GBool SplashFont::getGlyph(Guint c, int xFrac, int yFrac,

         SplashGlyphBitmap *bitmap) {

  SplashGlyphBitmap bitmap2;

  int size;

  Guchar *p;

  int i, j, k;

  // no fractional coordinates for large glyphs or non-anti-aliased

  // glyphs

  if (!aa || glyphH > 50) {

    xFrac = yFrac = 0;

  }

  // check the cache

  if (cache) {

    i = (c & (cacheSets - 1)) * cacheAssoc;

    for (j = 0; j < cacheAssoc; ++j) {

      if ((cacheTags[i+j].mru & 0x80000000) &&

    cacheTags[i+j].c == c &&

    (int)cacheTags[i+j].xFrac == xFrac &&

    (int)cacheTags[i+j].yFrac == yFrac) {

  bitmap->x = cacheTags[i+j].x;

  bitmap->y = cacheTags[i+j].y;

  bitmap->w = cacheTags[i+j].w;

  bitmap->h = cacheTags[i+j].h;

  for (k = 0; k < cacheAssoc; ++k) {

    if (k != j &&

        (cacheTags[i+k].mru & 0x7fffffff) <

        (cacheTags[i+j].mru & 0x7fffffff)) {

      ++cacheTags[i+k].mru;

    }

  }

  cacheTags[i+j].mru = 0x80000000;

  bitmap->aa = aa;

  bitmap->data = cache + (i+j) * glyphSize;

  bitmap->freeData = gFalse;

  return gTrue;

      }

    }

  } else {

    i = 0; // make gcc happy

  }

  // generate the glyph bitmap

  if (!makeGlyph(c, xFrac, yFrac, &bitmap2)) {

    return gFalse;

  }

  // if the glyph doesn't fit in the bounding box, return a temporary

  // uncached bitmap

  if (!cache || bitmap2.w > glyphW || bitmap2.h > glyphH) {

    *bitmap = bitmap2;

    return gTrue;

  }

  // insert glyph pixmap in cache

  if (aa) {

    size = bitmap2.w * bitmap2.h;

  } else {

    size = ((bitmap2.w + 7) >> 3) * bitmap2.h;

  }

  p = NULL; // make gcc happy

  for (j = 0; j < cacheAssoc; ++j) {

    if ((cacheTags[i+j].mru & 0x7fffffff) == cacheAssoc - 1) {

      cacheTags[i+j].mru = 0x80000000;

      cacheTags[i+j].c = c;

      cacheTags[i+j].xFrac = (short)xFrac;

      cacheTags[i+j].yFrac = (short)yFrac;

      cacheTags[i+j].x = bitmap2.x;

      cacheTags[i+j].y = bitmap2.y;

      cacheTags[i+j].w = bitmap2.w;

      cacheTags[i+j].h = bitmap2.h;

      p = cache + (i+j) * glyphSize;

      memcpy(p, bitmap2.data, size);

    } else {

      ++cacheTags[i+j].mru;

    }

  }

  *bitmap = bitmap2;

  bitmap->data = p;

  bitmap->freeData = gFalse;

  if (bitmap2.freeData) {

    gfree(bitmap2.data);

  }

  return gTrue;

}